A hard disk device has conventionally been used in equipment that processes information such as a computer. In recent years, the hard disk device is coming to be mounted on a home appliance such as a television set or a video recorder, and automotive electronic equipment in addition to being used as an external storage device of a computer.
A conventional hard disk device 200 illustrated in FIG. 15 houses a drive mechanism in a casing body 201. The drive mechanism includes a spindle 203 that rotates and drives a hard disk 202 being a recording medium (the spindle is rotated by a motor not illustrated in the drawing), a carriage 205 that supports a magnetic head 204 to record information in the hard disk 202 and read out the information, and pivots over a surface of the hard disk 202, a VCM (Voice Coil Motor) 206 that causes the carriage 205 to pivot precisely to control the scan of the magnetic head 204, and a pivot axis 207 that is fixed to the casing body 201 and connects the casing body 201 and the carriage 205. The pivot axis 207 has, for example, a substantially columnar shape, and has the configuration of a bearing.
The carriage 205 pivots on the pivot axis 207 as a center axis over the surface of the hard disk 202. A tolerance ring is used to fix between the carriage 205 and the pivot axis 207. The carriage 205 is fixed to the pivot axis 207, which prevents the power of the VCM 206 applied for the pivoting of the carriage 205 to be transferred to the casing body 201.
The tolerance ring has a ring shape formed of a flat plate-shaped member and obtained by curving the flat plate-shaped member almost into a circle along a predetermined direction. After the tolerance ring is inserted into an opening of the carriage 205, the pivot axis 207 is pressed into the tolerance ring. As such a tolerance ring, a tolerance rings including convex contact portions protruding toward the outer periphery side are disclosed (see, for example, Patent Literature 1 to 4). The contact portions of the tolerance ring as disclosed in Patent Literatures 1 to 4 are pressed against a side surface of either the carriage 205 or the pivot axis 207 to fix between the carriage 205 and the pivot axis 207.